It's honestly pretty rare for places to not have one in the US unless you're in the downtown part of a major city. Sometimes when walking downtown, it feels like every shop's bathrooms are staff-only.
The ADA has bathroom/stall quantity requirements in the US for certain types of businesses. Our machine shop almost had to put in more toilets despite us having 3 toilets and 3 employees. I believe it's based off of square footage. We are also required to have 28 parking spots for literally no reason.